The man suffered serious injuries at Mercy XS, on Prince of Wales Road, when officers were called to the venue following reports of a disturbance inside the club at about 1.45am.

A handful of people were involved in an argument, which started on the dance floor, and a 20-year-old man was hit on the side of his head, believed with a bottle, which caused an arterial bleed to the head.

It comes just weeks after a 42-year-old front-line police constable underwent surgery in hospital after another assault in the city, which resulted in a female officer also being assaulted. This reignited the debate over the city’s late night drinking culture. Click here for more.

Detective sergeant Andy Barker, from Norwich CID, said: “This was a very serious incident which has left a man with severe injuries which will require surgery today.”

The victim was taken to the Norfolk and Norwich University Hospital where he is awaiting surgery and is described as being in a stable condition.

Several people were thrown out of the club and police dealt with a second incident outside the nightclub where a 19-year-old man was assaulted by being punched in the face. The man suffered a bloody nose and was given first aid at the scene.

Four men were arrested shortly after the incident and were taken to Wymondham Police Investigation Centre where they remain in custody.

Two 20-year-olds and two other suspects aged 24 and 27, will be questioned on suspicion of assault causing grievous bodily harm. The 27-year-old was further arrested in connection with the second incident which happened outside the venue.

Police have now launched an investigation and detectives are keen to hear from anyone who may have been at the club and witnessed either incident.